St. John's wort is the target of a mainstream media attack that industry experts say is the result of a misinterpreted scientific study. On April 10, the Journal of the American Medical Association published a study comparing sertraline (known as the pharmaceutical Zoloft), St. John's wort (Hypericum perforatum) and a placebo for treating moderate to major depression.
Thirty-two percent of the patients who took placebo improved, while 25 percent of the patients who took Zoloft and 24 percent of the patients given St. John's wort improved. The results, researchers wrote in JAMA, showed "on the two primary outcome measures, neither sertraline nor H. perforatum was significantly different from placebo."
But the media fixated on St. John's wort's failure, not sertaline's. Washington Post announced "Herbal Cure's Worth Questioned."
"This study falls into the one-third of studies about clinical depression [concluding that certain treatments] don't work," said Steven Dentali, Ph.D., vice president for scientific and technical affairs at the American Herbal Products Association in Silver Spring, Md. "If there was no Zoloft in the study, then you could say that St. John's wort failed. If there was no placebo in the study, then you could say that St. John's wort and Zoloft work just as well. But with both of those in the study together, you can't say that St. John's wort doesn't work unless you're prepared to say that Zoloft doesn't work. And the fact is, there's plenty of studies on both those products to show that they are effective."
Results are only meaningful if the patient population responds properly to the positive control, said John Cardellina, Ph.D., vice president of botanical sciences and regulatory affairs for the Council for Responsible Nutrition in Washington, D.C. Data in this study should correlate to results of other sertraline studies.
"[Sertraline provides] an internal control to make sure the study's results are meaningful," Cardellina said. "The placebo group is a negative control. They got nothing and they should respond as if they got nothing, but we all know there's a placebo effect.
"The problem is that sertraline didn't do any better than placebo. In fact, it did worse in the two primary outcome measures of the trial. To any rational scientist, it suggests that the trial was no good. The results are basically null." Cardellina said it is unwise to draw a conclusion when subjects don't respond to the positive control.
Also at issue, Cardellina said, is that St. John's wort was used to treat a condition for which it is not recommended.
"The National Center for Complementary and Alternative Medicine, it seems to me, has a mission of proving or disproving that complementary therapies work. If that's truly their mission, then what they should do is investigate a particular therapy the way it's intended to be used. When the NIH set out to design this trial in 1996-97, the original plan was to test St. John's wort [for treating] mild to moderate depression," Cardellina said. Instead, NIH tested St. John's wort in patients with moderate to major depression.
"I'm questioning why the NIH would spend $4.3 million of taxpayers' money to test St. John's wort for something it's not recommended for," Cardellina said. "CRN had a press briefing last June when we realized this trial was targeted wrongly. [We] tried to precondition the media, to prewarn them that this was going to be an issue and that we expected this trial to fail."
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